Having a fresh memory of my data structures uni course the talk felt like a lecture. A big difference is that you explained it way better than my docent ever could and since university focused on Java it was very interesting to see the comparison to php. Well done :)

His satin American English delivered a hugely interesting story. Kudo’s for making a difficult subject understandable in less than half an hour ánd making a point with it in PHP. I still think quality assurance is even more important for PHP, but this topic definitely deserves more attention. The talk itself was quite relaxed and Jurriën expertly answered the few questions that came his way.

Ten years have gone by since I heard about big-Oh, big-Omega and big-Theta. Because I didn't had a real use case for them I apparently forgot all about them, and as the slides evolved my memory came back (thank God).
I really enjoyed the presentation because it gave me a deeper insight in why you should use the different SPL structures. Some real use cases would have been welcome in when to use each. Jurriën basically said "reason with your logic and try to figure it out."

That people with no Math background found it hard(er) to follow is normal, the talk was labeled: "advanced".

About the speaker, well he was very clear to understand and did a great job promoting the usage of these SPL datastructures, which thx to this talk I am going to re-visit.

Very good talk and very easy to follow speaker.
The math was way over my head and I think most of the attendees. The presentation might do better with a little less theoretical information.
Also a bit more information how to use the different structures in PHP in reality would be nice. What structure to use in what situation for instance?